Life cycle assessment of integrated waste management systems towards carbon neutrality and environmental sustainability

Abstract

This study develops a comprehensive framework for evaluating the environmental impacts of municipal solid waste (MSW) management in Thailand using Life Cycle Assessment (LCA). The framework covers collection, transportation, treatment, and avoided product utilization, considering different cluster sizes and technologies. Four conceptual scenarios were modeled: reference, current, waste management master plan, and improvement scenarios incorporating centralized and on-site systems. Results show that landfilling and incineration are major contributors to global warming, acidification, and eutrophication, while recycling and energy recovery technologies, including refuse-derived fuel (RDF) with waste-to-energy (WTE), substantially reduce impacts. Effective strategies vary by cluster size. For large clusters, optimal integration includes anaerobic digestion, composting, RDF with WTE, recycling, and landfilling. Medium clusters benefit from composting, RDF with WTE, recycling, and landfilling, whereas small clusters are best served by on-site home composting, incineration with WTE, recycling, and landfilling. A diversion of 95 % of waste from landfills, combined with a 30 % recycling rate, can lower climate change impacts by nearly 200 %. Sensitivity analysis indicates that reducing MSW transport distances further decreases impacts. Applying spatial differentiation in Life Cycle Impact Assessment (LCIA) and using different LCIA methods yielded consistent trends. Overall, the proposed framework supports the development of carbon-neutral MSW management systems by optimizing technology integration, maximizing recycling and energy recovery, and minimizing landfill disposal. The cluster-based approach offers tailored solutions for developing countries, significantly mitigating greenhouse gas emissions and other environmental impacts.